Loading...
This is What We Have Learned 2Loading...
5th Grade AMP 22-23Topic 8 & 12
Multiplying Fractions
Ratios
By: Miranda, Ignacio, Denisse, and Ana Regina
Topic 8-1
Multiplying a Fraction and a Whole Number
Find 3/5 of 15, or 3/5 x 15.
15 divided by 5 = 3, so 1/5 x 15 = 3
Since 3/5 is 3 times 1/5,
3/5 x 15 = 3 x ( 1/5 x 15) = 3 x 3 =9
3/5 x 15 = 9
15 divided by 5 = 3, so 1/5 x 15 = 3
Since 3/5 is 3 times 1/5,
3/5 x 15 = 3 x ( 1/5 x 15) = 3 x 3 =9
3/5 x 15 = 9
Examples:
4/5 x 20 = 16
6/7 x 14 = 12
4/5 x 20 = 16
6/7 x 14 = 12
Topic 8-2
Estimating Products
Lesson:8-2
When you are working with fractions and mixed numbers, you can estimate using rounding, compatible numbers, or compatible benchmark fractions.
1/6 x 19 = 3
4/7 x 10 = 5
16 x 4/9 = 8
Topic 8-3
Multiplying Fractions
1 step.- Multiply the numerators and denominators. Simplify if needed.
Example:
Example:
3/4 x 2/5 = (3 x 2)
(4 x 5)
(4 x 5)
=6/20
=3/10
=3/10
You can also check for cross products to simplify
5/7 x 3/10 = 3/14
4/7 x 1/2 = 2/7
Topic 8-4
Examples:
Multiplying mixed numbers
4 1/2 x 16= 72
6 x 3 1/4= 19 1/2